Lab 12

Question 1

Natural selection describes

Answer 1

Differential survival and reproduction

Question 2

As a result of natural selection what changes (evolutionary adaptation)

Answer 2

Populations change over generations and increase the frequency of traits suited to the environment

Question 3

Selective advantage

Answer 3

A trait that increases fitness

Question 4

Three general outcomes for natural selection on a population

Answer 4

Stabilizing selection
Directional selection
Disruptive selection

Question 5

Stabilizing selection

Answer 5

Favors intermediate phenotype sand typically occurs in more stable environments where extreme phenotypes selected against

Question 6

Directional selection

Answer 6

Shifts overall makeup of the population by selecting for one extreme

Common with environment changes

Question 7

Disruptive selection

Answer 7

Balancing of two contrasting phenotypes

Occurs in patchy environments

Question 8

Sexual selection

Answer 8

Specific form of natural selection in which individuals with certain traits are more likely than other individuals to obtain mates

Question 9

Biological species concept

Answer 9

Group of populations whose members have potential to interbreed with one another in nature to produce fertile offspring

Question 10

Prezygotic barriers vs. post zygotic

Answer 10

Block interbreeding before fertilization

Block interbreeding after fertilization

Question 11

Temporal isolation

Answer 11

When mating occurs at different seasons or times of the day

Question 12

Habitat isolation

Answer 12

When populations live in different habitats and do not meet

Question 13

Behavioral isolation

Answer 13

When little it no sexual attraction exists between populations

Question 14

Mechanical isolation

Answer 14

When structural differences prevent fertilization

Question 15

Gametic isolation

Answer 15

Egg and sperm fail to unite

Question 16

Reduced hybrid viability

Answer 16

Hybrid zygotes fail to develop to sexual maturity

Question 17

Reduced hybrid fertility

Answer 17

When hybrids do not produce functional gametes

Question 18

Hybrid breakdown

Answer 18

When hybrids of the next generation are feeble or sterile

Question 19

Evolution

Answer 19

Genetic composition changes over generations

Question 20

Evidence scientists have gathered to support theory

Answer 20

Homology (similarity in form or structure due to common ancestry)
Fossil record ( ordered sequence of fossils) 
Biogeography (distribution of species in geographic space and evolutionary time )
Molecular biology (study of hereditary background of an organism that is documented in DNA)